The invention relates to a motor vehicle having a front and a rear bumper, having a stiff floor structure and having body parts which laterally bound a passenger compartment. At least one energy-absorbing impact element which contributes to the transverse stiffening of the motor vehicle is arranged in the region of the front seats of the passenger compartment.
It is known from German Patent Document DE 28 16 318 C2 and DE 39 28 869 A1 additionally to arrange, in a motor vehicle with a stiff floor structure, a transverse stiffening structure over the width of the motor vehicle in the region of the front seats at the height of the bumpers of an impacting vehicle. This transverse stiffening structure has energy-absorbing impact elements in the side doors. The weight of the motor vehicle is increased by the provision of a transverse stiffening structure in addition to the stiff floor group.
An object of the invention is to create a motor vehicle, of the type mentioned above, which has adequate stiffness relative to side impact loads but without complicated additional devices.
This object is achieved according to preferred embodiments of the invention in that a stiff floor structure is arranged in a common plane at the height of the bumpers and a plurality of energy-absorbing impact elements, which are distributed over the length of the passenger compartment, are provided in the side body parts at the height of the floor structure. Because the floor structure is already arranged at the height of the bumpers, additional transverse stiffening is avoided in this region. Because of the arrangement of the side impact elements over the length of the passenger compartment, the motor vehicle is sufficiently protected against side impact loads over the whole of the side regions.
The advantages of prior art arrangements can therefore be achieved with a substantially reduced outlay and without a substantial increase in the weight of the vehicle. This is because only the energy-absorbing impact elements, whose weight is relatively small due to their structure, are required as additional elements. Plastic or aluminum honeycombs, plastic foams, aluminum extrusion profiles or aluminum or steel sheet-metal elements are exemplary elements employed as the impact elements.
The measures according to the invention are of particular advantage in the case of four-door vehicles because the occupants of the vehicle are protected against side impact loads both in the region of the front seats and in the region of the rear seats. In addition, the USA safety standards for which additional stiffening tubes were previously necessary in the side doors, are already satisfied by means of the measures according to the invention. The actual passenger compartment is displaced upwards by the invention because it adjoins the floor structure in an upwards direction.
In a preferred embodiment of the invention, the height of the impact elements corresponds to the height of the floor structure and their width corresponds approximately to the distance between the outer skin of the respective side body part and the side edge of the floor structure. By this means, a force path exists immediately between the impact elements and the floor structure in the case of a side impact so that lateral deformations cannot occur without corresponding acceptance of the deformation energy.
In a further embodiment of the invention, the impact elements are part of the side body parts. In consequence, the impact elements can already be provided within the carcass of the side body parts--of the side doors, for example.
In a further embodiment of the invention, the impact elements are configured as assembly parts which can be inserted in the side body parts.
In the case of embodiments as assembly parts, the structure and material of the impact elements can be individually selected to suit the desired deformation characteristic.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.